http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Functional diversification of the two C-class MADS box genes OSMADS3 and OSMADS58 in Oryza sativa.
Yamaguchi, Takahiro,Lee, Dong Yeon,Miyao, Akio,Hirochika, Hikohiko,An, Gynheung,Hirano, Hiro-Yuki American Society of Plant Physiologists 2006 The Plant cell Vol.18 No.1
<P>The C-class MADS box gene AGAMOUS (AG) plays crucial roles in Arabidopsis thaliana development by regulating the organ identity of stamens and carpels, the repression of A-class genes, and floral meristem determinacy. To examine the conservation and diversification of C-class gene function in monocots, we analyzed two C-class genes in rice (Oryza sativa), OSMADS3 and OSMADS58, which may have arisen by gene duplication before divergence of rice and maize (Zea mays). A knockout line of OSMADS3, in which the gene is disrupted by T-DNA insertion, shows homeotic transformation of stamens into lodicules and ectopic development of lodicules in the second whorl near the palea where lodicules do not form in the wild type but carpels develop almost normally. By contrast, RNA-silenced lines of OSMADS58 develop astonishing flowers that reiterate a set of floral organs, including lodicules, stamens, and carpel-like organs, suggesting that determinacy of the floral meristem is severely affected. These results suggest that the two C-class genes have been partially subfunctionalized during rice evolution (i.e., the functions regulated by AG have been partially partitioned into two paralogous genes, OSMADS3 and OSMADS58, which were produced by a recent gene duplication event in plant evolution).</P>
LEE, SANG-KYU,JEON, JONG-SEONG,BÖ,RNKE, FREDERIK,VOLL, LARS,CHO, JUNG-IL,GOH, CHANG-HYO,JEONG, SUK-WON,PARK, YOUN-IL,KIM, SUNG JIN,CHOI, SANG-BONG,MIYAO, AKIO,HIROCHIKA, HIROHIKO,AN, GYNHEUNG,CHO, Blackwell Publishing Ltd 2008 Plant, cell and environment Vol.31 No.12
<P>ABSTRACT</P><P>During photosynthesis, triose-phosphates (trioseP) exported from the chloroplast to the cytosol are converted to sucrose via cytosolic fructose-1,6-bisphosphatase (cFBPase). Expression analysis in rice suggests that OscFBP1 plays a major role in the cytosolic conversion of trioseP to sucrose in leaves during the day. The isolated <I>OscFBP1</I> mutants exhibited markedly decreased photosynthetic rates and severe growth retardation with reduced chlorophyll content, which results in plant death. Analysis of primary carbon metabolites revealed both significantly reduced levels of sucrose, glucose, fructose and starch in leaves of these mutants, and a high accumulation of sucrose to starch in leaves of rice plants. In the <I>oscfbp1</I> mutants, products of glycolysis and the TCA cycle were significantly increased. A partitioning experiment of <SUP>14</SUP>C-labelled photoassimilates revealed altered carbon distributions including a slight increase in the insoluble fraction representing transitory starch, a significant decrease in the neutral fraction corresponding to soluble sugars and a high accumulation of phosphorylated intermediates and carboxylic acid fractions in the <I>oscfbp1</I> mutants. These results indicate that the impaired synthesis of sucrose in rice cannot be sufficiently compensated for by the transitory starch-mediated pathways that have been found to facilitate plant growth in the equivalent <I>Arabidopsis</I> mutants.</P>